General Anesthesia Disrupts Complex Cortical Dynamics in Response to Intracranial Electrical Stimulation in Rats

Autor(es)

Arena, A. ^[1] ; Comolatti, R. ^[2] ; Thon, S. ^[1] ; Casali, A. G. ^[2] ; Storm, J. F. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Oslo, Dept Mol Med, N-0372 Oslo - Norway

^[2] Univ Fed Sao Paulo, Inst Sci & Technol, BR-12247014 Sao Jose Dos Campos - Brazil

• Tipo de documento: Artigo Científico
• Fonte: ENEURO; v. 8, n. 4 JUL-AUG 2021.
• Citações Web of Science: 1

Resumo

The capacity of human brain to sustain complex cortical dynamics appears to be strongly associated with conscious experience and consistently drops when consciousness fades. For example, several recent studies in humans found a remarkable reduction of the spatiotemporal complexity of cortical responses to local stimulation during dreamless sleep, general anesthesia, and coma. However, this perturbational complexity has never been directly estimated in non-human animals in vivo previously, and the mechanisms that prevent neocortical neurons to engage in complex interactions are still unclear. Here, we quantify the complexity of electroencephalographic (EEG) responses to intracranial electrical stimulation in rats, comparing wakefulness to propofol, sevoflurane, and ketamine anesthesia. The evoked activity changed from highly complex in wakefulness to far simpler with propofol and sevoflurane. The reduced complexity was associated with a suppression of high frequencies that preceded a reduced phase-locking, and disruption of functional connectivity and pattern diversity. We then showed how these parameters dissociate with ketamine and depend on intensity and site of stimulation. Our results support the idea that brief periods of activity-dependent neuronal silence can interrupt complex interactions in neocortical circuits, and open the way for further mechanistic investigations of the neuronal basis for consciousness and loss of consciousness across species. (AU)

• Processo FAPESP: 16/08263-9 - Padronização, validação e caracterização de uma nova medida de complexidade cerebral
• Beneficiário: Adenauer Girardi Casali
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores
• Processo FAPESP: 17/03678-9 - Padronização do índice de complexidade perturbacional para o estudo da conectividade efetiva talamocortical
• Beneficiário: Renzo Comolatti
• Modalidade de apoio: Bolsas no Brasil - Mestrado